1. Technical Field
The present invention relates to a method of forming a stacked-layer wiring, a stacked-layer wiring, and an electronic element.
2. Background Art
Wirings and electrodes used for semiconductor elements and electronic circuits can be formed by using a photolithographic technique. The photolithographic technique employs an exposure apparatus having high precision processing such as a stepper, and a vacuum apparatus for forming layers, and etching. The photolithographic technique requires expensive equipment, and further the number of processes becomes greater and the process becomes complex, and further material use efficiency becomes low, with which manufacturing cost increases.
Manufacturing cost can be reduced by using a printed electronics technology. As to the printed electronics technology, functional ink or paste such as fine metal particles is printed on a substrate base directly to form conductive patterns, and various printing methods can be used for the printed electronics technology.
For example, a patterning method using an inkjet method (or liquid droplet discharge method) can be used for the printed electronics technology. Specifically, liquid such as ink dispersed with fine particles is applied on a substrate base directly using an inkjet method, and then a curing process using heat processing and a laser irradiation process is conducted to form a conductive layer or film. This method can simplify the process and can enhance material use efficiency. Further, this method does not require material for patterning such as a photoresist used for the photolithographic technique, with which manufacturing cost can be reduced.
However, as to conventional inkjet methods, liquid droplets discharged on the substrate base may spread after the impact onto the substrate base, with which fine patterns are difficult to form on the substrate base. Further, conventional inkjet methods are difficult to respond to a demand of enhanced density and enhanced function device, and a demand of enhanced density wirings/electrodes and enhanced fine patterns for the device. Further, as to the inkjet method, when electrodes are stacked, a position of lower layer electrodes and a position of upper layer electrodes need to be aligned with high precision.